thinkphp5.0安装phpword扩展失败，怎么办？

Question

报以下错误：

Running composer update phpoffice/phpword
Loading composer repositories with package information
Updating dependencies
Your requirements could not be resolved to an installable set of packages.

  Problem 1
    - topthink/think-installer v1.0.12 requires composer-plugin-api ^1.0 -> foun
d composer-plugin-api[2.0.0] but it does not match the constraint.
    - topthink/framework v5.0.21 requires topthink/think-installer ~1.0 -> satis
fiable by topthink/think-installer[v1.0.12].
    - topthink/framework is locked to version v5.0.21 and an update of this pack
age was not requested.

You are using Composer 2, which some of your plugins seem to be incompatible wit
h. Make sure you update your plugins or report a plugin-issue to ask them to sup
port Composer 2.

Installation failed, reverting ./composer.json and ./composer.lock to their orig
inal content.

Answer 1

有包不支持你的 composer 2，需要用 composer 1 安装

composer self-update --1

安装 composer 1，若要安装 composer 2 可使用

composer self-update --2

Answer 2

使用composer self-update --1降版本后提示，咋整